Selective signaling system



. My 8, 1945.. M P TTS 2,375,383

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SELECTIVE SIGNALING SYSTEM Filed Jan. 17, 1929 15 Sheets-Sheet s.

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SELECTIVE S IGNALING SYSTEM Filed Jan. 17, 1929 15 Sheets-Sheet 7 7 av:J44 347 Hj-NQNALH U Search Room May s, 1945. M F s 2,375,333

SELECTIVE SIGNALING SYSTEM Filed Jan. 17 1929 15 Sheets-Sheet 8 A770 EYJSearch Room May 8, 1945. M. POTTS 2,375,383

SELECTIVE smmum SYSTEM Filed Jan. 17, 1929 15 Sheets-Sheet 9 human? 91JW ATTO 5w Search Room May 8, 1945. P0175 2,375,383

SELECTIVE SIGNALING SYSTEM Filed Jan. 17; 1929 15 Sheets-Sheet; 1O

W g I y I I I -r-v 7 T- T T 15 Sheets-Sheet 12 mlkwftl BY 9! J ATT L. M.POTTS SELECTIVE SIGNALING SYSTEM Fil'ed Jan. 17, 1929 May 8, I945.

May 8, 1945.

L. M. PoTTs 2,375,383

SELECTIVE SIGNALING SYSTEM Filed Jan. 17 1929 15 Sheets-Sheet is WWEFPW-ATT NEYJ W a e y 8, 1945- L. M. POTTS SELECTIVE SIGNALING SYSTEM FiledJan. 17 1929 15 Sheets-Sheet 15 INVENTOR. Jamar Poll;

Patented May 8, 1945 SELECTIVE SIGNALING SYSTEM Louis M. Potts,Evanston, 111., assignor to "roletype Corporation, Chicago, 111., acorporation of Delaware Application January 17 1929, Serial No. 333,161

49 Claims.

This invention relate. to selective signaling systems, and isparticularly adapted to the selective control of remotely disposed stockand commodities quotation boards from a central dispatching station,although the various combinations, sub-combinations and elements are notlimited to such uses.

The recent development of 'high speed tickers, has rendered thearrangement heretofore in use in which the quotations received from thetransmitting station are posted manually by attendants impractical andentirely inadequate to keeppace with the increased volume of businessnow being transacted. To handle this large volume of business, automaticmeans are necessary which indicate the quotations just as the quotationsare received, independently of any manual operation by an attendant.

Accordingly, a primary object of the invention is to provide a selectivesignaling system for indicating quotations at a.plurality of remotestations under control of a central dispatching station which is simple,reliable and accurate.

Another object of the invention is to provide methods and apparatus forperforming remote control, distributing, indicating and like operationsadapted to the remote automatic indication and recording of stockquotations and other selective control uses.

A further object of the invention is to provide novel indicating andrecording methods and apparatus.

Still another object of the invention is to provide novel circuitarrangements to selectively operate a plurality of indicators individualto items to be indicated.

A still further object of the invention is to provide novelsynchronizing means for selective and automatic remote control systems.

Further objects of the invention are to provide novel transmitting,selecting, and receiving equipment in telegraph systems, and which areespe- Fig. l is a schematic outline of one embodiment 4 of the improvedremote. control as applied to a stock quotation distribution system.

Fig. 2 is a front view of one embodiment of a single stock indicatingunit.

Fig. 3 is a circuit diagram of the transmitter and key board mechanismfor use in the preferred Fig. 5 is a detailview of the key board shownin Fig. 4 with the lock shown in the released position.

Fig. 6 is a detailed view of the restoring mechanism for the lock onsaid key board.

Fig. 7 is a fragmentary top view of said key board.

Fig. 8 is a diagrammatic view illustrating codes employed in thepreferred embodiment of the invention.

Figure 9 is a diagrammatic view of an automatic tape transmitter and thetransmitting circuit' therefor for use in a modified form of theinvention.

Figure 10 is a partial top view of said auto-- matic tape transmittershowing the perforated tape.

Figure 11 is a detailed view of the'tape feed mechanism for said tapetransmitter.

Figure 12 is a detailed view of a single group of control leversemployed in said tape transmitter.

Figure 13 is a schematic view of a receiving distributor utilized withthe invention.

Figure 14 is a circuit diagram of the translating relays ina preferredform of receiving circuit for the invention.

Figure 15 is a circuit diagram of a stock selector and also of a form ofindicator control circuit for use in the invention.

Figure i6 is a circuit diagram of receiver including the receivingdistributor for step by step indicators utilized in a modified form ofthe inv vention.

Figure 17 shows a circuit diagram of the translating circuits for stepby step indicators.

Figure 18 shows the circuit diagram for the step by step indicators.

Figures 19 and 20 are fragmentary views showing the preferred formsofstep by s p p indicators for the invention.

Figure 21 is a circuit diagram of selectively operated stock tickers.for use in the stock quotation system. c

Figure 22 is a fragmentary view of the tape with records on it made by aselected stock ticker.

Figure 23 is an arrangement of the sheets of drawings showing a completekey board system.

Figure 24 is an arrangement of the sheets of drawings showing a completeautomatic tape system.

Figure is an arrangement of the sheets of drawings showing a completesending and re ceiving circuit with step by step. indicators, key boardtransmission and circuit for selectively operated recording printers.

Figure 26 is an arrangement of sheets of drawings showing completesending and receiving circuit with direct key board transmission andcoordinate operation of cross magnetic indicators.

Figure 27 is a schematic diagram showing principles of a modified formof indicator of the cross magnetic type for use in the system.

Figure 28 is a showing of the field windings for the cross magneticindicators shown i Figure 27.

Figure 29 is a broken view of the cross mag- I netic indicator.

Figures 30, 31 and 32 are diagrams showing the directions of theresultant field in the cross magnetic indicator shown in Figure 27.

Figure 33 is a perspective view of the cross magnetic indicator showinga lock mechanism.

Figure 34 shows a volt meter modified type of indicator with voltageregulator which may be used in the system.

Figure 35 shows a further modification of the indicator employing adouble solenoid with an operating circuit.

Figure 36 is a diagram showing the pull at various points in thesolenoids of the indicator shown in Figure 35.

Figures 37 to 40 show the detail mechanism for operating the selectorbars in the preferred form of the invention.

Figure 41 shows the detail of the mounting for a stock unit.

Figure 42 is a fragmentary plan view of the preferred form of stockselectors.

Figure 43 is a perspective view of the stock selectors shown in Figure42.

Figure 44 is a coordinate selector for cross magnetic indicators.

Figure 45 shows details of the latch for the selector shown in Figure 44and Figures 46 and 47 show details of the lock for the cross magneticindicator shown in Figure 44.

General description of system Apreferred embodiment of the systememployed in carrying out the invention is disclosed in Figure 1 in whicha transmitter I, for generating code combinations of impulses iselectrically connected over the conductor 2 to a series of transmittingor repeating relays 3 to I, provided with individual armatures 8 to l2respectively operating between individual pairs of contacts l3 and I4.Although, as shown. polar relays are employed, it will be understoodthat these relays may be of any preferred construction.

Contacts 13 are all multipled over the conductor l5 and extend throughresistance I6 to the negative side of a sourc of energy I! which isgrounded at l8. The contacts I! are similarly multipled and connectedover conductor l9 through the resistance 20 to the positive side of asource of power 2| grounded at 22. The resistances l6 and 20 preventexcessive flow of current over these conductors in the event of anyshort circuit or other trouble on the signaling line.

Each of the armatures 3 to I2 is connected to an individual signalingline such as lines 23 and 24 each of which extends to a receiving set aswill be described hereinafter. These receiving sets may be remotelydisposed with respect to the transmitter station or at some adjacentpoint, this depending on the desired location of the stock quotationboards to be operated.

It will be clear from the above description that those armatures 8 to l2which are in engagement with their upper contacts 13 complete circuitsfrom the negative side of the source of energy I! to their individualsignaling lines and those armatures in engagement with their lowercontacts l4 complete circuits from the positive side of the source ofenergy 2|. In the present case, this source of energy is shown as twodirect current generators, although it is understood that any other wellknown source of energy as for example a storage battery may be utilizedand that the connection may be made to either side of the battery with agrounded tap at the center as is well known in the signaling art.

When the transmitter shown diagrammatically at l is operated, each ofthe transmitting relays 3 to I will be operated in accordance therewithfor operating their armatures between contacts l3 and H. A code isaccordingly transmitted by each of these transmitting relays. Thus, forexample, as the armature 8 is successively operated, in accordance withthe code generated by transmitter I, contacts l3 and I4 will variablyassociate the sources of negative and positive energy I! and 2| to theline 23 with which the armature 8 is associated and accordingly codecombinations of impulses will be transmitted thereover. Similarlytransmitting relay 1 will operate its armature [2 to transmit the samecode over signaling line 24.

The line 23 extends to a plurality of receiver and distributormechanisms 21 to 29 located at a station 3|, which station either may belocal with respect to the transmitter I or at some point remotetherefrom. In the present instance, these distributors are assumed to belocal and accordingly no repeater is interposed between the line 23 anddistributors 21 to 23. The receiving mechanisms 21, 28 and 29diagrammatically shown are, as will be described hereinafter, arrangedto receive the code combinations of impulses transmitted over the line23 and distribute them to selecting mechanisms. Although thesedistributors are shown connected in series, it will be understood that aparallel connection may be used if desired. As shown, the distributor 21is connected over the conductor 32 to selector mechanisms 33, 34, and35. Each of the selector mechanisms 33 to 35 is individual to a stockquotation board section 36, 31 and 38 respectively. In the presentembodiment, these stock quotation sections are shown made up of 48 stockunits or items 39, six being arranged horizontally and eight verticallyin each unit. Each of these units 39 represents an item, the quotationof which is to be indicated and as will be described in detailhereinafter, comprises indicators made up of numerals.

As will be described in more detail hereinafter. the impulsesdistributed by the receiver and distributor 21 selectively operate theselector mechanism 33 which in accordance with the received code selectsone of the units 39 for operating the gggaguwu.

indicators thereon. As will be understood by those skilled in the art,the selector 33 is arranged to operate in response to those codes formaking the necessary selections in the section 36, whereas the selector34 will operate in response to diflerent codes to make the selection ofthe units in section 31 and so on. Thus although all of the selectors 33to 35 will operate in response to the signals received over the line 23through the receiver and distributor 21, only one of these will beefiective in response to any one code for making a selection in thisparticular section,

In addition to operating the indicators in sections 36 to 38 thereceiver and distributor 21 is also connected over the conductor 4| tothe selector 42 individual to the section 43. As will be clear from theabove in each of the sub-stations there may be one or more sections ofquotation boards 36 to 38 and 43 each of which comprises any desirednumber of stock units or items.

tributor 21 is also connected over the conductor 45 to a printing magnet46 which controls a printing mechanism 41 of any well known type forprinting on a tape 48. As will be clear, the magnet 48 is operatedselectively in accordance with a code transmitted over the conductor 45from the receiver and distributor 21 to record the stock quotationswhich are indicated on the stock quotation board.

Similarly each of the other receivers and distributors 28 and 23connected in series with distributor 21 operate in response to codesreceived over line 23 for operating indicators and printers connectedthereto as shown in connection with distributor 21.

It will be clear from the above that the other relays 4 to 1 similarlyoperated under control of the transmitter I, may be connected throughtheir armatures 3 to l2 over individual conductors to remote pointswhere similar receivers and distributors are located for distributingthe impulses to selectors operating similar stock quotation indicators.Thus for example, the armature I2 of the transmitter relay 1 is shownconnected over the conductor 24 to the receiving and repeating relay 52at a remote station 53. Armature 54 of relay 52 operating between itsupper and lower contacts connected to the negative and positive side ofa source of power, is connected over conductor 55 to a distributor 56similar to distributor 21 located at station 3|. A conductor 51 is shownconnected to the distributor 56 and to a selector mechanism 58associated with the stock quotation section 58 for selecting theindicators 39 thereon in accordance with the code received by thedistributor 56. A second distributor 6| in parallel with distributor 56over line 55 is connected over conductor 62 to a selector 63 foroperating the indicators 38 in a section 64.

In the above description, a general diagrammatic circuit diagram of thesystem is described none of the details of the mechanism beingspecifically shown. As will now be clear, the transmitting arrangement,with the relays 3 to I and the generators l1 and 2|, are located at theprin- Search Room cipal ofllce or master station which might be in thetelegraph office or in the stock exchange itself. From this station,there radiate a number of conductors such as 23 and 24, the former ofwhich may extend to receiving equipment 21 to 29 located in the samecity as the master station I.

The receiving apparatus 21 may control any number of boards, a largeboard with a great many sections 36 to 38 and a small board with fewsections 43, the latter possibly for use of a specialist. There may bealso operated from the receiving apparatus 21, stock tickers forprinting the quotations of any stock or selected list of stocks, whichfeature of the invention has been made the subject matter of divisionalapplication Serial No. 663,483, filed March 30, 1933, which matured intoPatent No. 2,225,657, granted December 24, 1940.

The conductor 24 may extend to a distant city where a similar series ofbrokers ofiices may have boards which are controlled from the centraloffice I. Any sort of network may be built up in this manner coveringthe entire country so that all the boards and selective tickers for a.given exchange may be operated from a single transmitting point.

One method contemplated for operating such a system, is to have one ormore editing operators who will use a standard ticker tape, designatingthe high "low, etc. This tape will then be passed to the sendingoperator or operators, who will transmit the designations indicated. Itwill probably be desirable or essential for this Operation and formonitoring purposes, to provide the complete board in the central ofiicefor the guidance of the editing operators.

Transmitter A detailed description of the transmitter key board, relay.transmitter distributors, selector and item indicators making up onecomplete circuit of this system will now be given.

The key board mechanism Figure 3, comprises eight sets of key boardsections 1| to 18. Key board sections 1| to 13 each comprise a completeset of standard telegraph typewriter key levers 19, one for each letterof the alphabet. Key board sections 14 to 16 each comprise ten keylevers 8| one for each of the ten digits from 0 to 9. The key boardsection 11 comprises seven key levers 82 one for each of the fractionsfrom to and an extra blank key lever 83 for the start operation as willbe described more fully hereinafter, and the key board section 18comprises four key levers 84 to 81 one each for closing, opening, highand low respectively.

These key board sections may be of any well known construction in whichthe levers operate contacts in various combinations in the manner shownin the patent to Potts 1,299,608 issued April 8, 1919, or the patent toKleinschmidt, 1,567,392 issued December 29, 1925, for generating codcombinations of impulses although it will be understood that these arecited as illustration and that any other transmitter such as thekeyboards used for call indicators in automatic telephone exchanges maybe utilized if preferred.

In the illustrated embodiment the key levers 13 on key board 1|selectively operate five contactors 9| between contacts 32 and 93 invarious combinations. As described in the patents referred to above,each key lever 13 will operate these contactors in individualcombinations.

Contacts 92 are connected in multiple over conductor 94 to the negativeside of the source of energy 95 and through a resistance 96 to ground at91. Contacts 93 are connected in mul tiple over a conductor 98 to theositive side of the source of energy 99 connected through a. resistanceI to ground at IOI. As shown in the drawings, the key levers on thesecond and third key boards 12 and 13, control five similar contactors9I operating between contacts 92 and 93. These are operated in the wellknown manner in various combinations in accordance with the particularkey lever depressed for closing various combinations of circuits fromthe sources of energy 95 and 99 to a. distributing mechanism to be laterdescribed.

The levers 8| on the fourth key board 14 comprising the ten digits,selectively control four contactors I95 operating between contacts I06and I01. These contacts are connected in multiple and to the sources ofpower 95 and 99. Upon depression of any one of the key levers 8| in thekey bank 14, combinations of four of these contacts are closed and as iswell known in the art provide sixteen different combinations of impulsesin accordance with the key levers depressed. Inasmuch as there are tenkey levers in this bank, it will be clear that the number of codecombinations available are in excess to that necessary. The same is trueof the key banks 15 and 1B. The key bank 11 similarly controlscombinations of three contactors for providing the necessary seven codesfor the fractions and key levers 84 to 81, each control one contactorI05.

Associated with the banks of keys H to 18 are unlocking magnets III oneindividual to each of the banks. Upon operation of a key lever 19 in thebank H a locking mechanism, to be described, operates to lock theoperated key in position and lock the remaining levers on the bankagainst operation. The magnet III associated with the bank operatesimmediately after the transmission of the code controlled by theoperated key for releasing the operated key from its operated positionand releasing the other levers to permit operation of any one thereof.This arrangement prevents the operation of more than one key during thetransmission of an individual code signal.

The details of this latching mechanism are disclosed in Figures 4 to 7to which reference will now be had. As shown each of the key levers 19is pivotally mounted on a pin I I5, and is provided with downwardlyprojecting lugs I I6 on the under surface thereof. As will be understoodby those skilled in the art, various combinations of these lugs areprovided on each key lever, these lugs coacting with levers II1 pivotedon pins H8 and operating the contact closers such as 9| between theircontacts 92 and 93. In response to the operation of key lever 19 shownin Figure 4, two of these lever arms II1 are operated to in turn operatethe contact closers 9I associated with them from contact 92 with whichthey are nor mally associated to their opposite contacts 93 Similarlyeach of the other key levers operate individual combinations of thelevers II1.

Extending upwardly from each of the key levers 19 is a curved lug member"I rovided with a horizontal section I22. As shown in Figure 4 thehorizontal section I22 extends a distance insumcient to normally engageuniversal member I23 of a locking lever I24 when all the key levers 19are in unoperated position. Lever I24 is pivoted on pin I25 suitablymounted on the frame work I of the key board and has secured thereto oneend of a spring I26 the other end of which is secured to the frame work.The universal member I23 extends adjacent all of the lugs I2I on thelevers 19.

Spring I25 normally maintains the lever I24 in engagement with thelatching lever I21, pivotedly mounted on the pin I28 suitably carried inthe frame and is normally urged into engagement with the locking leverI24 by the spring I29, one end of which is secured to the extension I3Iof the locking lever I21 and the other end to the frame work. Thelocking lever I21 is provided with an extension I32 on which is carrieda uni versal member I33 extending beneath all of the key levers 19.

Under normal conditions with all of the key levers in a non-operatedposition, the spring I29 maintains the universal member I33 inengagement with the lower sides of all of the key levers 19. In thatposition the latching lever I21 is in engagement with the lever I24 andacts against the tension of spring I25 to maintain the universal memberI23 just out of engagement with the horizontal extension I22 of the lugI2I of each of the key levers 19. Upon the operation of any one of thesekey levers, the universal member I33 is pushed downwardly as shown inFigure 5 and the locking lever I21 is rocked against the tension ofspring I29 until it disengages the lever I24. The spring I25 thereuponrocks the lever arm I24 about its pivot I25 moving the universal memberI23 to the position shown in Figure 5 in operative relation with thehorizontal extension I22 of each of the lugs I2I on the key levers 19.These non-operated levers 19 are now locked against operation by theuniversal member I23 and the operated lever is locked in position.

As shown in Figures 6 and 7 restoring or unlocking magnet I II isprovided with an armature I34 rotatable with pin I25 on which it ismounted. Upon energization of the restoring magnet III in a manner to bedescribed, its armature I34 is rocked to in turn rotate pin I25.Latching lever I24 is thereby rotated in a clockwise direction restoringit to its normal non-operated condition, in turn restoring the operatedkey lever and conditioning the other key levers for operation.

Referring again to Figure 3, it will be noted that each of the contactcontrollers 9| is connected over conductors such as I4I individualthereto to individual segments I42 on the distributor I43. DistributorI43 comprises a first sect on composed of a segmental ring I 44 and asolid ring I45 bridged by brushes I45 and I41 and a second sectioncomprising a segmental ring I48 and a solid ring I49 bridged by thebrushes I50 and I5I The first segment I53 on ring I44 connected to thenegative side of a battery is a stop segment and the second segment I54connected to the pos tive side of a battery is a start segment. The nextfifteen segments on ring I44 are connected to the fifteen contactcontrollers 9I on the first three key banks H to 13, the succeedingtwelve segments are connected to the contact controllers I05 of the keybanks 14 to 15, the next three segments are connected to the contactcontrollers on the key bank 11 and the next four segments are connectedto the contact controllers on the key bank 18. The lowermost segment onring I44 cooperates with the start and stop segments I53 and I54 as willbe described in connection with the completed systems. The solid ringI45 is connected to a signaling line I55 extending to a receivingapparatus for transmitting the code combinations generated by key boardsH to 18 thereto.

By this arrangement for each cycle of operation of this giant start-stopdistributor, there is transmitted three letter characters, threenumbers, a fraction, and a control signal. It will be noted that thesame combination of impulses may be used for a letter, for a number andfor a fraction, and instead of determining which character is desired bya shift signal, this is determined by the position of the combinationwith respect to the start impulse.

The ring I48 is provided with eight segments I56. Each of these segmentsI56 is 50 positioned with respect to the preceding five segments on thesegmental ring I44 that the brushes I50 and II pass thereover when inrotation, immediately after the brushes I46 and I41 have moved overthese five segments. The first segment I56 is connected over theconductor I 59 to the electro magnet III associated with the first bankof keys 1I. Similarly each of the other segments on ring I48 isconnected to the associated magnets III, The solid ring I49 is connectedto the positive side of a source of energy. When the brush I50 wipesover the segment I56 a circuit is completed through the electro magnetIII indicated which upon energization restores the latching mechanism asdescribed in connection with Figures 4 to 7 for permitting therestoration of the key levers.

Due to the large number of segments on the distributor and the characterof the signaling, some form of associate speed control in addition tothe start-stop feature is needed as the synchronism for this type ofdistributor must be considerably more accurate than is required for theusual five or six unit code start-stop distributor. Such a control willnow be described. The brushes I46, I41, I58 and I5I are carried on armI6I in operative relation with the friction clutch I62 of any well knownconstruction. The friction clutch I62 is carried by and rotatable withthe drivin shaft I63 which also carries a gear I64 secured in a wellknown manner for rotation with the shaft. A spring I65 presses thefriction clutch I62 against the arm I6I providing a mechanical frictionclutch connection to the drive shaft I63. The gear I64 meshes with thepinion I66 carried on the drive shaft I61 of a direct current motor I68comprising an armature I69 and field winding I18 connected at oneterminal through a resistance I'll to the posit ve side of a source ofenergy I12 and at the other terminal to round. Upon the same shaft withthe armature I69 is an alternating current motor I13 which is connectedthrough the lamp I 14 to the secondary of a trans former I15.

The primary of this transformer is connected to two contacts I16 and I11of a leaf spring I18 mounted on one of the tines of a tuning fork I19.The tuning fork I19 of any well known construction is connected to thepositive side of a source of power. The circuit for an electromagnet I8Iis alternately closed through a contact controlled by the leaf springI82 mounted on the other tine of the tuning fork I19. When the tines arespread apart, the circuit for the electromagnet I8I is closed frompositive battery through fork I19, through contact I82 (which is nowclosed), through winding of magnet I8I and thence through resistance toground, and this magnet thus is energized to bring the fork tinestogether. In the spread position, current flows through contact I11 andthe right hand half of the primary of transformer I to ground. With thetines of the fork close together, the leaf spring I18 closes the contactI16 and completes a circuit through the other half of the primarywinding and in the opposite direction. In this manner periodicalreversals of current are produced in the primary of transformer I15which in turn induces alternating currents of a predetermined frequencyin the secondary of the transformer which fiows through the alternatingcurrent motor I13.

As is well known in the art, the tines of the tuning fork I19 can bemade to vibrate at a predetermined frequency and are then kept vibratingat this frequency by the electromagnet I8I. Accordingly currents of afixed frequency flow through the winding of motor I13. The winding ofmotor I13 of any well known construction produces rotation, as is wellknown, at a speed determined by the frequency of the current flowingtherethrough. This frequency control system is more clearly described inU. S. Patent No. 1,764,316 and is illustrated in Figure 1 of thatpublication. In this manner the motor I68 is kept rotating at an almostconstant speed, the actual power for driving the shaft I61 beingsupplied by the motor winding I68. Accordingly an almost constantrotating speed for the distributor I43 is obtained. The flickering ofthe lamp I14 observed in connection with the rotation of the distributorwill in a well known manner, determine the relative speed at which themotor is rotating.

As shown, the arm I6I is normally latched against rotation by a latchingarmature I9I pivotally mounted on the frame I92 of the electromagnetI93. When the electromagnet I93 is energized in a manner to bedescribed, it moves armature I9I from engagement with the arm I6I andreleases the latter for rotation. The electromagnet I93 is connectedover the conductor I94 to a contact controller I95 on the key bank 11.This contact is as described above, arranged to be closed upon theoperation of any one of the key levers 82 or blank lever 83 on bank 11.

The operation of the key board transmitter will now be described. Inorder to transmit a quotation of a particular item, the operator firstdepresses a key bar on each of the first three key banks 1| to 13 fortransmitting a code to select the indicator individual to the particularitem for which the quotation is to be transmitted. As will be describedhereinafter this code when received at the receiving station will selectthe indicator individual to the particular item desired. The operatorwill also depress one of the key bars on each of the banks 14 to 16which will transmit codes individual to the digits making up thequotation for the selected item. One of the levers 82 on the bank 11will also be operated to transmit a code for the fraction in thequotation and a key lever on bank 18 will be operated to transmit a codeindicating whether the quotation is close, opening, high, low or last.As has been described in detail above, upon the depression of any keylever in banks H to 18 the other key levers in each of these banks arelocked from operation and the depressed key levers are locked inoperated position.

Depression of any key lever 82 closes the contact I95. It will beunderstood that the blank lever 83 need only be depressed in the eventthat a fraction code is not to be sent. Inasmuch as the closing ofcontact I95 starts the distributor, the key on this bank should be thelast one operated. As a result of the closing of contact I95 a circuitis completed from ground through the contact I95 and over conductor I94through the winding

